Methods and apparatuses for system information transmission and system information reception in a wireless communication system

ABSTRACT

Embodiments of the present disclosure relate to a method and apparatus of data transmission in a wireless communication system and a method and apparatus of receiving data in a wireless communication system. The method of data reception comprises transmitting a request for the RRC message to the network node based on default transmission parameters; and receiving the RRC message from the network node at a predetermined time unit. With embodiments of the present disclosure, it is possible to request the RRC message when the terminal device need this message and therefore the RRC message transmission can be reduced and in turn, the inter-node interference can be limited, and the number of LBTs required for these signal transmissions can be reduced if they are transmitted on unlicensed spectrum.

FIELD OF THE INVENTION

The non-limiting and exemplary embodiments of the present disclosuregenerally relate to the field of wireless communication techniques, andmore particularly relate to a method and apparatus for transmittinginformation and a method and apparatus for receiving information.

BACKGROUND OF THE INVENTION

With the constant increase of wireless data services, licensed carrierresource is limited and hard to cope with the constantly increasing datatraffic. Thus, it is proposed to use unlicensed carrier resource fordata transmission, which could provide a large amount of frequencyresources in a cost effective way.

Recently, the 3rd Generation Partnership Project (3GPP) organization hadstarted standardization on Licensed-Assisted Access, which introducesthe data offloading from the licensed carrier resource to the unlicensedcarrier resource on small cells to deliver a data speed boost toterminal devices. For data transmission on the unlicensed carrier, itshall perform a Listen Before Talk (LBT) operation to detect whether thechannel is idle. The transmission on the unlicensed carrier can only beperformed when the LBT result shows that the channel is idle; otherwisethe transmission will not be performed on the unlicensed carrier.Therefore, the transmission opportunity in unlicensed spectrum islimited due to the LBT.

Usually, reference signals (such as a discovery signal (DRS)) and radioresource control (RRC) message (such as system information, pagingmessage, etc.) are both required to be transmitted to terminal deviceslike user equipment (UE). These signals often have differenttransmission periodicities and different time offsets and might havesome dependency therebetween. For example, the DRS, Mater InformationBlocks (MIB), System Information Blocks (SIB), and paging messages inlegacy LTE systems have different periodicities and different timeoffsets, and the DRS/MIB/SIB/paging have dependency among each other.This means that successful decoding of one signal might depend ondecoding of another signal and thus UE cannot get full systeminformation if some of the information cannot be received successfully.In such a case, it will impact the user experience substantially.Besides, there might be also an energy consumption issue and inter-nodeinterference issue as well.

In US application publication No. US20160165638A1, there is disclosed asolution for enhanced system access for E-UTRAN, in which a two-stagesystem information transmission solution and a reduced paging cycle areproposed. Particularly, in this application, in a first stage, firstsystem information common to each cell of a group of cells in an area isbroadcasted first; then second system information that can vary betweencells in the group is broadcasted; and the second system information isbroadcasted more frequently than the first system information.

In technical document RP-160870, New WI: Work Item on Standalone LTEoperation and dual connectivity operation in unlicensed spectrum,Ericsson, 3GPP RANP#72 meeting, it discloses a standard LAA to supportscheduling DRS, MIB and SIBs in a common subframe.

However, multiple LBT attempts will be still necessary for referencesignal and the RRC message transmission on unlicensed spectrum if theyare transmitted in different time instances and there might still beinter-node interferences due to these information transmissions.

SUMMARY OF THE INVENTION

In the present disclosure, there is provided a new solution forinformation transmission and information reception in a wirelesscommunication system, to mitigate or at least alleviate at least part ofthe issues in the prior art.

According to a first aspect of the present disclosure, there is provideda method of receiving information in a wireless communication system,wherein the information at least comprises a radio resource control(RRC) message. The method comprises transmitting a request for the RRCmessage to the network node based on default transmission parameters;and receiving the RRC message from the network node at a predeterminedtime unit.

According to a second aspect of the present disclosure, there isprovided a method of transmitting information, wherein the informationat least comprises a radio resource control (RRC) message. The methodcomprises receiving a request for the RRC message transmitted from aterminal device based on default transmission parameters; andtransmitting the RRC message to the terminal device at a predeterminedtime unit in response to the request for the RRC message.

According to a third aspect of the present disclosure, there is providedan apparatus for receiving information in a wireless communicationsystem, wherein the information at least comprises a radio resourcecontrol (RRC) message. The apparatus comprises an RRC requesttransmission module and an RRC message receiving module. The RRC requesttransmission module is configured to transmit a request for the RRCmessage to the network node based on default transmission parameters.The RRC message receiving module is configured to receive the RRCmessage from the network node at a predetermined time unit.

According to a fourth aspect of the present disclosure, there isprovided an apparatus of transmitting information, wherein theinformation at least comprises a radio resource control (RRC) message.The apparatus comprises: an RRC request receiving module and an RRCmessage transmission module. The RRC request receiving module configuredto receive a request for the RRC message transmitted from a terminaldevice based on default transmission parameters. The RRC messagetransmission module is configured to transmit the RRC message to theterminal device at a predetermined time unit in response to the requestfor the RRC message.

According to a fifth aspect of the present disclosure, there is provideda computer-readable storage media with computer program code embodiedthereon, the computer program code configured to, when executed, causean apparatus to perform actions in the method according to anyembodiment in the first aspect.

According to a sixth aspect of the present disclosure, there is provideda computer-readable storage media with computer program code embodiedthereon, the computer program code configured to, when executed, causean apparatus to perform actions in the method according to anyembodiment in the second aspect.

According to a seventh aspect of the present disclosure, there isprovided a computer program product comprising a computer-readablestorage media according to the fifth aspect.

According to an eighth aspect of the present disclosure, there isprovided a computer program product comprising a computer-readablestorage media according to the sixth aspect.

With embodiments of the present disclosure, it provides a new solutionfor information transmission and reception, in which the RRC message istransmitted in response a RRC message request from a terminal devicewhen the terminal device needs this message. In such a way, the RRCmessage transmission can be reduced and in turn, the inter-nodeinterference can be limited, and the number of LBTs required for thesesignal transmissions can be reduced if they are transmitted onunlicensed spectrum.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other features of the present disclosure will become moreapparent through detailed explanation on the embodiments as illustratedin the embodiments with reference to the accompanying drawings,throughout which like reference numbers represent same or similarcomponents and wherein:

FIG. 1 schematically illustrates a flow chart of a method of receivinginformation in a wireless communication system according to anembodiment of the present disclosure;

FIG. 2 schematically illustrates a flow chart of a method fordetermining default transmission parameters for the request according toan example embodiment of the present disclosure;

FIG. 3 schematically illustrates a flow chart of a method oftransmitting information in a wireless communication system according toan embodiment of the present disclosure;

FIG. 4 schematically illustrates a flow chart of a method of informationtransmission and reception in a wireless communication system accordingto a specific implementation of the present disclosure;

FIG. 5 schematically illustrates a block diagram of an apparatus forreceiving information in a wireless communication system according to anembodiment of the present disclosure; and

FIG. 6 schematically illustrates a block diagram of an apparatus fortransmitting information in a wireless communication system according toan embodiment of the present disclosure;

FIG. 7 further illustrates a simplified block diagram of an apparatus710 that may be embodied as or comprised in UE and an apparatus 720 thatmay be embodied as or comprised in a base station in a wireless networkas described herein.

DETAILED DESCRIPTION OF EMBODIMENTS

Hereinafter, the solution as provided in the present disclosure will bedescribed in details through embodiments with reference to theaccompanying drawings. It should be appreciated that these embodimentsare presented only to enable those skilled in the art to betterunderstand and implement the present disclosure, not intended to limitthe scope of the present disclosure in any manner.

In the accompanying drawings, various embodiments of the presentdisclosure are illustrated in block diagrams, flow charts and otherdiagrams. Each block in the flowcharts or blocks may represent a module,a program, or a part of code, which contains one or more executableinstructions for performing specified logic functions, and in thepresent disclosure, a dispensable block is illustrated in a dotted line.Besides, although these blocks are illustrated in particular sequencesfor performing the steps of the methods, as a matter of fact, they maynot necessarily be performed strictly according to the illustratedsequence. For example, they might be performed in reverse sequence orsimultaneously, which is dependent on natures of respective operations.It should also be noted that block diagrams and/or each block in theflowcharts and a combination of thereof may be implemented by adedicated hardware-based system for performing specifiedfunctions/operations or by a combination of dedicated hardware andcomputer instructions.

Generally, all terms used in the claims are to be interpreted accordingto their ordinary meaning in the technical field, unless explicitlydefined otherwise herein. All references to “a/an/the/said [element,device, component, means, step, etc.]” are to be interpreted openly asreferring to at least one instance of said element, device, component,means, unit, step, etc., without excluding a plurality of such devices,components, means, units, steps, etc., unless explicitly statedotherwise. Besides, the indefinite article “a/an” as used herein doesnot exclude a plurality of such steps, units, modules, devices, andobjects, and etc.

Additionally, in a context of the present disclosure, a user equipment(UE) may refer to a terminal, a Mobile Terminal (MT), a SubscriberStation (SS), a Portable Subscriber Station (PSS), Mobile Station (MS),or an Access Terminal (AT), and some or all of the functions of the UE,the terminal, the MT, the SS, the PSS, the MS, or the AT may beincluded. Furthermore, in the context of the present disclosure, theterm “BS” may represent, e.g., a node B (NodeB or NB), an evolved NodeB(eNodeB or eNB), a radio header (RH), a remote radio head (RRH), arelay, or a low power node such as a femto, a pico, and so on.

As mentioned hereinabove, in the existing solutions, a reference signaland RRC message transmissions still require multiple LBT attempts andalso cause inter-node interferences. Thus, in the present disclosure,there is provided a new solution of information transmission andreception to address these issues. In the present disclosure, it isproposed that a terminal device such as UE requests the RRC messagesbased on default transmission parameters when the terminal devicerequires the RRC message and the serving node such as NB or eNB cantransmit the RRC message to the requested terminal device when itreceives the request from the terminal device. Thus, the RRC message istransmitted only when it is required and therefore the RRC messagetransmission can be reduced and in turn, the inter-node interference canbe limited, and the number of LBTs required for these signaltransmissions can be reduced if they are transmitted on unlicensedspectrum. Hereinafter, the solution of information transmission andreception will be described in detailed with reference to the accompanydrawings as provided therein.

Reference is first made to FIG. 1, which schematically illustrates aflow chart of a method 100 of data receiving in a wireless communicationsystem according to an embodiment of the present disclosure. The method100 can be performed at a terminal device, for example UE, or other liketerminal devices

As illustrated in FIG. 1, first in step S101, a request for the RRCmessage is transmitted to the network node based on default transmissionparameters. In embodiments of the present disclosure, the RRC messagemay include any of RRC information elements, security controlinformation elements, mobility control information elements, measurementinformation elements, other information elements, Multimedia BroadcastMulticast Service (MBMS) information elements, Single Cell-Point ToMultipoint (SC-PTM) information elements, sidelink information elements,system information blocks (SIB), master information blocks (MIB), pagingmessage and other RRC messages newly defined in the future.

Hereinafter, only for illustration purposes, the MIB, and the SIB willbe described as the example of the RRC message; however, the skilled inthe art shall be noticed that the present disclosure is not limited tothese specific examples and it can be applied to any other kind of RRCmessage like paging messages as well.

The request for the RRC message can be transmitted in uplink controlchannel, for example, in Physical Random Access Channel (PRACH),Physical Uplink Control Channel (PUCCH), Physical Uplink Shared Channel(PUSCH), etc. In addition, the request for the RRC message may also betransmitted in uplink reference signals.

In embodiment of the present disclosure, the UE requests an RRC messageif the UE requires the RRC message and it does not receive the RRCmessage, thus at this time it does not learn RRC message transmissionparameters. Therefore, in the present disclosure, it is proposed totransmit the request for the RRC message using default transmissionparameters. Next, for illustration purposes, reference will be made toFIG. 2 to describe a method of determining the default transmissionparameters for the RRC message.

FIG. 2 schematically illustrates a flow chart of a method fordetermining default transmission parameters for the request according toan example embodiment of the present disclosure. The method 200 can beperformed at a terminal device, for example UE, or other like terminaldevices. As illustrated in FIG. 2, in step 201, the transmission poweris determined. The determination of the transmission power may be basedon for example, a predetermined target receive power and a referencesignal receive power. The reference signal receive power is a referencevalue and the predetermined or default target receive power can beobtained as well. Thus, by using the two parameters, it is possible todetermine the transmission power for the RRC message.

Then in step 202, a preamble sequence for the request is determinedbased on at least one of a cell identifier carried in the referencesignal, a selected preamble index, a preamble duration restriction and aselected preamble format. For example, it may first obtain a defaultpreamble set which are used for the RRC message, and the UE determines acell specific preamble set from the default preamble set based on a cellid carried in discovery reference signal (DRS). The UE then can choose apreamble index randomly or based on a predetermined rule. It may set apreamble duration restriction. For example, the preamble duration may berestricted to be 1 ms or any other suitable value. Next, a suitablepreamble format can be selected. Thus, it may decide a preamble sequencefor request from the cell specific preamble set based on the preambleindex, the preamble duration restriction, the selected preamble format.The preamble sequences for RRC messages can be legacy sequences, i.e.,those sequences used in the legacy systems. Or alternatively, thepreamble sequences for RRC messages can be newly defined cell specificsequence.

Next, in step 203, it may determine a configuration index for therequest. The configuration index may be a predetermined or defaultindex. Then the request for the RRC message can be transmitted from, forexample, the boundary of the subframe.

Thus, the UE can determine the default transmission parameters for theRRC message. However, it shall be noticed that the above-describedmethod is only given for a purpose of explanation and the presentdisclosure is not limited thereto. For example, the order of performingthe steps can be changed; each of the steps may be modified or be takenseparately to use with other different steps. All these changes do notdeviate from the spirit of the present disclosure and still fall withinthe scope of the present disclosure.

In response to the request for the RRC message, the serving node, likeeNB, will transmit a feedback containing the required RRC information tothe UE at a predetermined timing. Detailed operations about the eNB willbe described in the following context with reference to FIG. 3 and thuswill not be elaborated herein.

Next, reference is made back to FIG. 1, in step 102, the UE receives theRRC message at a predetermined time unit, for example, within apredetermined subframe. In other words, after the request for the RRCmessage is transmitted, the RRC message will be transmitted from the eNBand the UE can receive the RRC message in predefined time/frequencyresources. The RRC message can be carried by Physical Downlink ControlChannel (PDCCH) and/or Physical Downlink Shared Channel (PDSCH).

The response window size and/or the predetermined timing can be used andthey can be learned by the UE and thus the UE can obtain information inthe RRC message. In other words, the RRC message can be decoded based onat least one of a predetermined response window size and a predeterminedtransmission timing. In addition or alternatively, the UE also needs toknow the default scrambling value, and t_id and f_id value for CRCdescrambling RNTI. Since these information can predetermined or defaultand can be easily learned by the UE. Thus, the RRC message can beobtained and further downlink or uplink transmission can be furtherprocessed.

However, if the RRC message is not received successfully, the UE mayinitiate the retransmission of the request for the RRC message. In therequest retransmission, the power ramping and/or maximum transmissiontimes can be determined based on predefined default values, e.g. thosein the LTE specification.

In addition, the reference signal is useful in transmitting the RRCmessage. In embodiments of the present disclosure, the reference signalmay include any of, for example, a discovery signal, a cell referencesignal (CRS), channel status information reference signals (CSI-RS), aprimary synchronization signal (PSS), a secondary synchronization signal(SSS), or any other kind of reference signal. In an embodiment of thepresent disclosure, the UE can receive the reference signal which istransmitted periodically from the network node. This means that thereference signal like DRS can be transmitted periodically while the RRCmessage can be transmitted based on the UE's request.

Next reference is made to FIG. 3 to describe the operations at theserving node. FIG. 3 schematically illustrates a flow chart of a methodof transmitting information in a wireless communication system accordingto an embodiment of the present disclosure. The method 300 can beperformed at a serving node, for example a BS, like a node B (NodeB orNB).

As illustrated in FIG. 3, in step 301, the eNB receives a request forthe RRC message transmitted from a terminal device based on defaulttransmission parameters. In embodiments of the present disclosure, theRRC message may include any of RRC information elements, securitycontrol information elements, mobility control information elements,measurement information elements, other information elements, MultimediaBroadcast Multicast Service (MBMS) information elements, SingleCell-Point To Multipoint (SC-PTM) information elements, sidelinkinformation elements, system information blocks (SIB), masterinformation blocks (MIB), paging message and other RRC messages newlydefined in the future.

The request for the RRC message may be received in the uplink controlchannel, like PRACH, PUCCH, PUSCH, etc. In addition, the request for theRRC message may also be received in uplink reference signals.

The eNB blind decodes the request for the RRC message innon-transmitting subframes. If the eNB decodes the request successfully,in step 302, the eNB transmits the RRC message as a feedback to theterminal device at a predetermined time unit in response to the requestfor the RRC message. The feedback can be carried by PDCCH and/or PDSCH.It can use a default response window size which can be set to a defaultvalue, e.g. 1. The transmission timing can be predefined as well. Forexample, the feedback timing can be set to n+4, where n is the requesttransmission subframe index. The predefined transmission timing can alsobe the nearest following subframe meeting the required periodicity andoffset. As such, the worst case is a periodic RRC message transmission.

In addition, the reference signal can be transmitted to terminal devicesperiodically so that the terminal device can learn enough referencesignal information for transmitting the request for the RRC message. Inembodiments of the present disclosure, the reference signal may includeany of, for example, a discovery signal (DRS), a cell reference signal(CRS), channel status information reference signals (CSI-RS), a primarysynchronization signal (PSS), a secondary synchronization signal (SSS),or any other kind of reference signal.

For illustrative purposes, next reference will be made to FIG. 4 todescribe a whole system flow chart of the information reception andtransmission according to a specific embodiment of the presentdisclosure. In this specific implementation, the DRS will be taken as anexample of the reference signal and the system information containingSIB, MIB, etc. will be taken as an example of the RRC message. However,the skilled in the art shall appreciate that they are given only forillustration purposes, other reference signals and/or other RRC messagecan transmitted by using the solution as proposed herein as well.

First, at step 401, the eNB periodically transmits DRS. The UE can gettime/frequency synchronization and subframe index from the DRS based onDRS detection. When the UE requires the system information, then in step402, the UE monitors subframes potentially transmitting the systeminformation. For example, the UE can monitor the energy on subframesother than DRS subframes.

In step 403, it is determined whether the system is detected through themonitoring in step 402. If the energy is detected in a subframe, and thesubframe is possibly the system information transmission subframe (e.g.subframe 0), then UE may blind decode the subframe to obtain the systeminformation. Thus, the method directly goes to step 409 in which thesystem information can be used for further processing, for examplefurther uplink processing and/or further downlink processing. On theother hand, if it is determined that the UE fails to detect the systeminformation in potential subframes, i.e., no energy is detected and thesystem information is not available yet, the UE transmits PRACH based ondefault transmission parameters in step 404. The PRACH may contain aspecial indicator to indicate that it is related to a request for thesystem information. The default transmission parameters can bedetermined by, for example, using the method as described with referenceto FIG. 2 and thus will be not be elaborated herein.

In step 405, the eNB receives the PRACH from the terminal device andblind decodes the PRACH in non-transmitting subframes. If the PRACH isdecoded successfully, in step 406 the eNB may transmits the systeminformation as a feedback at the predetermined time instance. Thefeedback can be carried by using PDCCH and/or PDSCH. The defaultresponse window size can be used as set to a default value, e.g. 1. Thetransmission timing can be predefined as well. For example, the feedbacktiming can be set to n+4, where n is the PRACH transmission subframeindex. The predefined transmission timing can also be the nearestfollowing subframe meeting the periodicity and offset. As such, theworst case is a periodic system information transmission. The systeminformation can be carried in the PDSCH.

After the PRACH transmission, in step 407, the UE receives the systeminformation transmitted from the eNB at a predetermined subframe. Inother words, the UE receives the system information in predefinedtime/frequency resources and the UE can decode the system informationbased on at least one of the default response window size, predefinedtransmission timing, the default scrambling value and t_id and f_idvalue for CRC descrambling RNTI.

If the system information is successfully detected in step 408, thesystem information can be obtained and the method proceeds with step 409in which further downlink/uplink transmission can also be processed.

If the system information is not successfully detected in step 408, themethod goes back to step 402 to perform a PRACH retransmission. For thePRACH retransmission, the power ramping and/or maximum transmissiontimes can be determined based on predefined default values, e.g. by theLTE specification.

Thus, in the present disclosure, it is proposed that a terminal devicesuch as UE requests a RRC message based on default transmissionparameters when the terminal device requires this RRC message, and theserving node such as NB or eNB can transmit the RRC message to therequested terminal device when it receives the request from the terminaldevice. Therefore, the RRC message can be transmitted only when it isrequired and therefore the RRC message transmission can be reduced andin turn, the inter-node interference can be limited, and the number ofLBTs required for these signal transmissions can be reduced if they aretransmitted on unlicensed spectrum.

Besides, in the present disclosure, there are also provided apparatusesfor information reception and transmission in a wireless communicationsystem, which will be described next with reference to FIGS. 5 and 6.

FIG. 5 schematically illustrates a block diagram of an apparatus 500 forreceiving information in a wireless communication system according to anembodiment of the present disclosure. The apparatus 500 can beimplemented at a terminal device, for example UE, or other like terminaldevices.

In the embodiment as illustrated in the FIG. 5, the information at leastcomprises a radio resource control (RRC) message. As illustrated in FIG.5, the apparatus 500 may comprise: an RRC request transmission module501 and an RRC message receiving module 502. The RRC requesttransmission module 501 can be configured to transmit a request for theRRC message to the network node based on default transmissionparameters. The RRC message receiving module 502 can be configured toreceive the RRC message from the network node at a predetermined timeunit.

In an embodiment of the present disclosure, the apparatus 500 mayfurther comprise a time unit monitoring module 503. The time unitmonitoring module 503 can be configured to monitor potential time unitsfor transmitting the RRC message. In such a case, the requesttransmission module 501 may be further configured to transmit therequest in response to failing to find the RRC message in the monitoredtime units.

In another embodiment of the present disclosure, the apparatus 500 mayfurther comprise a message decoding module 504. The message decodingmodule 504 may be configured to decode the RRC message based on at leastone of a predetermined response window size and a predeterminedtransmission timing.

In a further embodiment of the present disclosure, the information mayfurther comprise a reference signal, the apparatus 500 may furthercomprise a reference signal receiving module 505. The reference signalreceiving module 505 may be configured to receive the reference signaltransmitted periodically from a network node.

In a still further embodiment of the present disclosure, the defaulttransmission parameters may be determined by at least one of:determining a transmission power based on a predetermined target receivepower and a reference signal receive power; determining a preamblesequence for the request based on at least one of a cell identifiercarried in the reference signal, a selected preamble index, a preambleduration restriction and a selected preamble format; and determining aconfiguration index for the request.

In a still further embodiment of the present disclosure, the messagereceiving module 502 may be further configured to receive the RRCmessage in PDCCH and/or PDSCH. Additionally or alternatively, therequest transmitting module 501 may be further configured to transmitthe request for the RRC message in the uplink control channel.

In another embodiment of the present disclosure, the apparatus 500 mayfurther comprise a retransmission initiation unit 506. Theretransmission initiation unit 506 may be configured to initiate theretransmission of the request for the RRC message in response to failingto obtain the RRC message successfully.

In a further embodiment of the present disclosure, the reference signalmay at least comprise a discovery signal and the RRC message maycomprise at least one of a master information block (MIB), a systeminformation block (SIB) and a paging message.

FIG. 6 further schematically illustrates a block diagram of an apparatus600 for transmitting information in a wireless communication systemaccording to an embodiment of the present disclosure. The apparatus 600can be performed at a serving node, for example a BS, like a node B(NodeB or NB).

In embodiment as illustrated in FIG. 6, the information at leastcomprises a radio resource control (RRC) message, and as illustrated inFIG. 6, the apparatus 600 comprises: an RRC request receiving module 601and an RRC message transmission module 602. The RRC request receivingmodule 601 can be configured to receive a request for the RRC messagetransmitted from a terminal device based on default transmissionparameters. The RRC message transmission module 602 can be configured totransmit the RRC message to the terminal device at a predetermined timeunit in response to the request for the RRC message.

In an embodiment of the present disclosure, the RRC message transmissionmodule 602 may be further configured to transmit the RRC message byusing at least one of a predetermined response window size andpredetermined transmission timing.

In another embodiment of the present disclosure, the RRC messagetransmission module 602 may be further configured to transmit the RRCmessage in PDCCH and/or PDSCH.

In a further embodiment of the present disclosure, the RRC requestreceiving module 601 may be further configured to receive the requestfor the RRC message in the uplink control channel.

In a still further embodiment the present disclosure, the informationfurther may comprise a reference signal and the apparatus 600 mayfurther comprise a reference signal transmission module 603. Thereference signal transmission module 603 can be configured to transmitthe reference signal to terminal devices periodically.

In a yet further embodiment of the present disclosure, the referencesignal may at least comprise a discovery signal and the RRC message maycomprise at least one of a master information block (MIB), a systeminformation block (SIB) and a paging message.

Hereinbefore, the apparatuses 500 and 600 are described with referenceto FIGS. 5 and 6. It is noted that the apparatuses 500 and 600 may beconfigured to implement functionalities as described with reference toFIGS. 1 to 4. Therefore, for details about the operations of modules inthese apparatuses, one may refer to those descriptions made with respectto the respective steps of the methods with reference to FIGS. 1 to 4.

It is further noted that the components of the apparatuses 500 and 600may be embodied in hardware, software, firmware, and/or any combinationthereof. For example, the components of apparatuses 500 and 600 may berespectively implemented by a circuit, a processor or any otherappropriate selection device. Those skilled in the art will appreciatethat the aforesaid examples are only for illustration not limitation andthe present disclosure is not limited thereto; one can readily conceivemany variations, additions, deletions and modifications from theteaching provided herein and all these variations, additions, deletionsand modifications fall the protection scope of the present disclosure.

In some embodiment of the present disclosure, apparatuses 500 and 600may comprise at least one processor. The at least one processor suitablefor use with embodiments of the present disclosure may include, by wayof example, both general and special purpose processors already known ordeveloped in the future. Apparatuses 500 and 600 may further comprise atleast one memory. The at least one memory may include, for example,semiconductor memory devices, e.g., RAM, ROM, EPROM, EEPROM, and flashmemory devices. The at least one memory may be used to store program ofcomputer executable instructions. The program can be written in anyhigh-level and/or low-level compliable or interpretable programminglanguages. In accordance with embodiments, the computer executableinstructions may be configured, with the at least one processor, tocause apparatuses 500 and 600 to at least perform operations accordingto the method as discussed with reference to FIGS. 1 to 4 respectively.

It shall be appreciated that although the DRS, the system informationincluding MIB, and the SIB are described hereinabove, these signals arejust given as examples for illustration purposes and in fact the presentdisclosure is not limited thereto. The idea of the present disclosurecan also be applied in any other reference signals like CRS, CSI-RS,PSS, SSS, etc., and any other RRC messages like paging messages RRCinformation elements, security control information elements, mobilitycontrol information elements, measurement information elements, otherinformation elements, MBMS information elements, SC-PTM informationelements, sidelink information elements, and other RRC messages newlydefined in the future.

While the present disclosure is mainly described with unlicensedspectrums and offer a great benefit thereto, the present disclosure isnot limited only to the unlicensed spectrums but can be applied normalcommunication and provide benefit of reduced inter-node interferences.

FIG. 7 further illustrates a simplified block diagram of an apparatus710 that may be embodied as or comprised in a terminal device such as UEin a wireless network and an apparatus 720 that may be embodied as orcomprised in a base station such as NB or eNB as described herein.

The apparatus 710 comprises at least one processor 711, such as a dataprocessor (DP) and at least one memory (MEM) 712 coupled to theprocessor 711. The apparatus 710 may further comprise a transmitter TXand receiver RX 713 coupled to the processor 711, which may be operableto communicatively connect to the apparatus 720. The MEM 712 stores aprogram (PROG) 714. The PROG 714 may include instructions that, whenexecuted on the associated processor 711, enable the apparatus 710 tooperate in accordance with embodiments of the present disclosure, forexample the method 100, 200. A combination of the at least one processor711 and the at least one MEM 712 may form processing means 715 adaptedto implement various embodiments of the present disclosure.

The apparatus 720 comprises at least one processor 721, such as a DP,and at least one MEM 722 coupled to the processor 721. The apparatus 720may further comprise a suitable TX/RX 723 coupled to the processor 721,which may be operable for wireless communication with the apparatus 710.The MEM 722 stores a PROG 724. The PROG 724 may include instructionsthat, when executed on the associated processor 721, enable theapparatus 720 to operate in accordance with the embodiments of thepresent disclosure, for example to perform the method 300. A combinationof the at least one processor 721 and the at least one MEM 722 may formprocessing means 725 adapted to implement various embodiments of thepresent disclosure.

Various embodiments of the present disclosure may be implemented bycomputer program executable by one or more of the processors 711, 721,software, firmware, hardware or in a combination thereof.

The MEMs 712 and 722 may be of any type suitable to the local technicalenvironment and may be implemented using any suitable data storagetechnology, such as semiconductor based memory devices, magnetic memorydevices and systems, optical memory devices and systems, fixed memoryand removable memory, as non-limiting examples.

The processors 711 and 721 may be of any type suitable to the localtechnical environment, and may include one or more of general purposecomputers, special purpose computers, microprocessors, digital signalprocessors DSPs and processors based on multicore processorarchitecture, as non-limiting examples.

In addition, the present disclosure may also provide a carriercontaining the computer program as mentioned above, wherein the carrieris one of an electronic signal, optical signal, radio signal, orcomputer readable storage medium. The computer readable storage mediumcan be, for example, an optical compact disk or an electronic memorydevice like a RAM (random access memory), a ROM (read only memory),Flash memory, magnetic tape, CD-ROM, DVD, Blue-ray disc and the like.

The techniques described herein may be implemented by various means sothat an apparatus implementing one or more functions of a correspondingapparatus described with one embodiment comprises not only prior artmeans, but also means for implementing the one or more functions of thecorresponding apparatus described with the embodiment and it maycomprise separate means for each separate function, or means that may beconfigured to perform two or more functions. For example, thesetechniques may be implemented in hardware (one or more apparatuses),firmware (one or more apparatuses), software (one or more modules), orcombinations thereof. For a firmware or software, implementation may bemade through modules (e.g., procedures, functions, and so on) thatperform the functions described herein.

Exemplary embodiments herein have been described above with reference toblock diagrams and flowchart illustrations of methods and apparatuses.It will be understood that each block of the block diagrams andflowchart illustrations, and combinations of blocks in the blockdiagrams and flowchart illustrations, respectively, can be implementedby various means including computer program instructions. These computerprogram instructions may be loaded onto a general purpose computer,special purpose computer, or other programmable data processingapparatus to produce a machine, such that the instructions which executeon the computer or other programmable data processing apparatus createmeans for implementing the functions specified in the flowchart block orblocks.

While this specification contains many specific implementation details,these should not be construed as limitations on the scope of anyimplementation or of what may be claimed, but rather as descriptions offeatures that may be specific to particular embodiments of particularimplementations. Certain features that are described in thisspecification in the context of separate embodiments can also beimplemented in combination in a single embodiment. Conversely, variousfeatures that are described in the context of a single embodiment canalso be implemented in multiple embodiments separately or in anysuitable sub-combination. Moreover, although features may be describedabove as acting in certain combinations and even initially claimed assuch, one or more features from a claimed combination can in some casesbe excised from the combination, and the claimed combination may bedirected to a sub-combination or variation of a sub-combination.

It will be obvious to a person skilled in the art that, as thetechnology advances, the inventive concept can be implemented in variousways. The above described embodiments are given for describing ratherthan limiting the disclosure, and it is to be understood thatmodifications and variations may be resorted to without departing fromthe spirit and scope of the disclosure as those skilled in the artreadily understand. Such modifications and variations are considered tobe within the scope of the disclosure and the appended claims. Theprotection scope of the disclosure is defined by the accompanyingclaims.

What is claimed is:
 1. A method performed by a terminal device, themethod comprising: transmitting, to a network device, a request for asystem information in a Physical Random Access Channel (PRACH), whereinthe transmitting the request comprises: transmitting a preamble for therequest in the PRACH, wherein the preamble is transmitted based on areference signal comprising primary synchronization signal (PSS), asecondary synchronization signal (SSS); and receiving the systeminformation from the network device based on a transmission timing,wherein the transmission timing is determined based a periodicity of thesystem information.
 2. The method of claim 1, further comprising:receiving the system information based on response window size and atransmission timing for the system information.
 3. The method of claim1, wherein the preamble is transmitted based on a preamble durationrestriction.
 4. The method of claim 1, wherein the receiving the systeminformation comprises: receiving the system information in PhysicalDownlink Control Channel (PDCCH) or Physical Downlink Shared Channel(PDSCH).
 5. The method of claim 1, further comprising: initiating aretransmission of the request for the system information in response tofailing to obtain the system information successfully.
 6. A methodperformed by a network device, the method comprising: receiving, from aterminal device, a request for a system information in a Physical RandomAccess Channel (PRACH), wherein the receiving the request comprises:receiving a preamble for the request in the PRACH, wherein the preambleis transmitted based on a reference signal comprising primarysynchronization signal (PSS), a secondary synchronization signal (SSS);and transmitting the system information to the terminal device based ona transmission timing, wherein the transmission timing is determinedbased a periodicity of the system information.
 7. The method of claim 6,wherein the transmitting the system information comprises transmittingthe system information based on response window size and a transmissiontiming for the system information.
 8. The method of claim 6, wherein thetransmitting the system information comprises transmitting the systeminformation in in Physical Downlink Control Channel (PDCCH) or PhysicalDownlink Shared Channel (PDSCH).
 9. A terminal device comprising: amemory configured to store one or more instructions; and a processorconfigured to: transmit, to a network device, a request for a systeminformation in a Physical Random Access Channel (PRACH), wherein theprocessor is further configured to: transmit a preamble for the requestin the PRACH, wherein the preamble is transmitted based on a referencesignal comprising primary synchronization signal (PSS), a secondarysynchronization signal (SSS); and receive system information from thenetwork device based on a transmission timing, wherein the transmissiontiming is determined based a periodicity of the system information. 10.The terminal device of claim 9, wherein the processor is furtherconfigured to receive the system information based on response windowsize and a transmission timing for the system information.
 11. Theterminal device of claim 9, wherein the preamble is transmitted based ona preamble duration restriction.
 12. The terminal device of claim 9,wherein the processor is further configured to receive the systeminformation in Physical Downlink Control Channel (PDCCH) or PhysicalDownlink Shared Channel (PDSCH).